Magnetic recording media are widely employed in areas such as recording tapes, video tapes, and floppy disks. Particulate magnetic recording media have a layer configuration comprising a nonmagnetic support over which is formed a magnetic layer comprising a ferromagnetic powder and a binder. High levels of various characteristics are demanded of particulate magnetic recording media, such as electromagnetic characteristics, running durability, and running properties. That is, a greater ability to reproduce the original sound is demanded of audio tapes employed in the recording and reproduction of music, and good ability to reproduce an original image and good electromagnetic characteristics are demanded of video tapes.
By contrast, magnetic recording media having a magnetic layer imparted with high coercivity are known to afford good electromagnetic characteristics; for example, see Japanese Unexamined Patent Publication (KOKAI) No. 2000-268343. This magnetic recording medium sets the ratio (Hc/Br) of coercivity (Hc) to residual magnetic flux density (Br) in the magnetic layer to the range from 560 to 1240 kA/(T·m) and sets the coercivity (Hc) in the magnetic layer to the range from 159 to 239 kA/m to achieve good electromagnetic characteristics.
However, in an environment demanding better durability, such as when recording and reproducing with a magnetic head rotating at high speed, even the magnetic recording medium described in Japanese Unexamined Patent Publication (KOKAI) No. 2000-268343 does not afford fully satisfactory durability. In particular, in the devices employed in the high-density recording of recent years, the speed at which the magnetic head rotates has been increased. In digital video tape recorders, the rotational speed of the magnetic head is at least 9,600 rpm. Since such rotational speeds are far greater than the 1,800 rpm of popular analog video tape recorders and the 5,000 rpm of professional devices, the rate at which the magnetic head slides over the magnetic recording medium is quite high.
Accordingly, when recording and reproduction are conducted with such a magnetic head rotating at high speed on the magnetic recording medium of Japanese Unexamined Patent Publication (KOKAI) No. 2000-268343, it is necessary to further enhance the durability of the magnetic recording medium of Japanese Unexamined Patent Publication (KOKAI) No. 2000-268343.